National Toxicology Program

National Toxicology Program
https://ntp.niehs.nih.gov/go/9625

Target Organs and Levels of Evidence for TR-103

Bioassay of Fenthion for Possible Carcinogenicity (CASRN 55-38-9)

Chemical (Study Title)
CASRN
Peer Review DatePrimary UsesRoute/Exposure LevelsStudy Laboratory
Fenthion
55-38-9
10/25/1978Insecticide, ascaricide, cholinesterase inhibitor (Merck 1989); one of the organophosphate pesticides. Associated with tobacco: reported either as a natural component of tobacco, pyrolysis product (in tobacco smoke), or additive for one or more types of tobacco products.Dosed-Feed
0,10,20 PPM/50 PER GROUP
Gulf South Research Institute

Levels of Evidence

Male Rats: Negative
Female Rats: Negative
Male Mice: Equivocal
TypeOrgan/Tissue (Lesion)
Neoplastic Lesions
  • Skin: (SARCOMA OR FIBROSARCOMA OR RHABDOMYOSARCOMA)
Female Mice: Negative


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